Apparatus for introducing a device through a bore hole casing



Feb. 17, 1970 J. B. DAHMS ETAL 3,495,875

I APPARATUS FOR.INTRODUCING A DEVICE THROUGH A 3035: HOLE cpsme originalFiled Mardh "11, 1966 INVENTOR! JAMES 8. Ohms 3720M R 50mm A ORNEYSUnited States Patent US. Cl. 299- 3 Claims ABSTRACT OF THE DISCLOSUREApparatus for introducing devices such as flexible conduits, meters andthe like through a bore hole casing to a subterranean cavity asdescribed. The apparatus comprises concentric pipes, one housing thedevice, the other acting as a protective cover while the pipes are inthe bore hole casing. An opening in the inner pipe and constructionpermitting the pipes to be separated in a vertical direction,

allows for the introduction of the device to the cavity when the cavityis reached by both pipes. Means for firmly attaching the outer pipe tothe casing are also described.

This is a division of applicants copending application Ser. No. 533,558,filed Mar. 11, 1966 and now Patent No. 3,400,980.

This invention relates to placing down hole mechanisms in a subterraneancavity. It more specifically relates to novel apparatus for insertingdown hole mechanisms through a cased bore hole to a subterranean cavityand methods for the use thereof.

Very often in subterranean operations, notably in solution mining, it isdesired to place a variety of mechanisms ranging from simple pipeextensions to complicated gadgetry in a subterranean cavity. The onlyaccess to such a cavity may be through one or more cased bore holes oflimited diameter. In solution mining of salts, e.g., NaCl, KC], trona,or similar extractable materials, the casings employed are rarely inexcess of 12 inches internal diameter. More often, the casings employedare between about 4 and about inches in diameter. In typical solutionmining operations where a cased bore hole is disposed throughsubterranean formations to communicate with a cavity located, e.g., lessthan 1,000 to 5,000 or more feet beneath the surface of the earth, 7inch casings are commonly employed. Pushing down hole mechanisms throughthis limited access is hazardous to the equipment. The difiicult andhazardous nature of the operation severely limits the type of equipmentwhich can be disposed in a bore hole. Typically only very ruggedmechanisms of a simple nature have been inserted through a long casingto a a subterranean cavity. The present invention provides simple yetetfective means for introducing delicate and/ or complicated down holemechanisms to a subterranean cavity.

Particularly useful adaptations of the claimed apparatus are thoseemployed to deliver delicate solvent carrying devices to a subterraneancavity. In a typical solution mining operation, a cased bore hole isprovided through the earth to an extractable deposit. One or more tubesare then disposed through the bore hole to communicate with the deposit.These tubes provide additional conduits for fluid flow. Typically,solvent is introduced to the deposit through the annulus between thecentrally disposed tubing and the casing of thebore hole to contact theextractable deposit. Solution laden with extracted minerals is thenwithdrawn from the deposit to the surface of the earth through thecentrally disposed conduit thereby forming a cavity in the extractabledeposit.

At first, when the cavity is small, a solution mining system is normallyquite uneconomical. As the cavity size is increased, the economics ofthe operation significantly improve. The efiiciency and productivity ofa solution mining cavity may often be greatly improved by developing thecavity in selected directions to produce a cavity of a desired shape.The desired shape of a cavity depends largely on the configuration andmineral composition of the mineable and adjacent deposits.

Economics, productivity, and efliciency of a solution mining operationalso generally improve when the injection point at which solvent isintroduced to the cavity is separated by a substantial distance from theeffluent point at which solution is withdrawn from the cavity. Thisseparation results in an improved fiowpattern in the cavity. Lateralseparation of the injection and withdrawal points is particularlybeneficial. Such lateral separation is most conveniently obtained byproviding in the cavity horizontal extensions of the injection and/orwithdrawal conduits.

It is often desirable to develop a plurality of cavities until theycommunicate with each other. The internal piping or tubing can then beremoved from the bore holes communicating with the respective cavities.One such bore hole can then function as the solvent input conduit whilethe laterally separated bore hole functions as the efiluent withdrawalconduit. It is usually desirable to accomplish this connection ofseparated bore holes as quickly as possible. Connection of separatedbore holes is greatly facilitated by preferentially extracting thedeposit at the base of a bore hole towards a separated bore hole.Extraction in a selected direction is encouraged by providing in thecavity lateral extensions to the supply conduit or conduits oriented inthe desired direction.

Copending application Ser. No; 533,489, filed Mar. 11, 1966, teaches theintroduction of flexible conduits to a solution mining cavity. The tubeis oriented and extended in the earth to provide a lateral extension ofthe casing from which it originates. Commonly assigned, copendingapplication Ser. No. 533,518, filed Mar. 11, 1966, teaches theintroduction of telescoping rigid conduits to a cavity. The nested tubesare oriented and extended to provide lateral extensions of the injectionand/or withdrawal casin'gs. The conduits disclosed in the aforementionedcopending applications are subject to damage as they are introduced downa bore hole. The apparatus of the present invention provides protectivecarrying means for these delicate extendable conduits. The claimedapparatus is also useful to protectively introduce other delicatedevices besides solvent delivery systems such as flow diverters,photographic equipment, electronic gear, sample retrieval devices, etc.

The invention will be more readily understood with reference to theaccompanying drawings of which FIGURES 1 and 2 illustrate an embodimentof the claimed device in which the hatch is covered by an outerconcentric pipe section.

It is recognized that a casing may not always be disposed in a strictlyvertical orientation in practice. Often a bore hole is provided to asubterranean deposit in a direction with both a vertical and asignificant horizontal component. The direction of the bore hole isoften altered from time to time between the earths surface and thesubterranean terminus of the bore hole. The overall vertical componentis normally much greater than the overall horizontal component, however.Hence, in the instant disclosure, the invention is described withreferece to vertical bore holes. The solvent supply or other devicesintroduced down a bore hole in the apparatus of this invention andsubsequently reoriented are accordingly described as being in an uprightor vertical position. The invention includes within its scopeembodiments in which such devices are disposed in a horizontal or someother direction, provided the axis of the carrier is approximatelyparallel to the axis of the bore hole.

FIGURES l and 2 illustrate an embodiment in. which the carryingapparatus of this invention comprises essentially two concentric pipes.The outer pipe 90 is held in relation to the inner pipe 91 by means suchas a I hook 92 and lug 93. Referring to FIGURE 1, the inner pipe carriesthe mechanism to be introduced down down the bore hole casing 94. outerpipe serves as a shield or cover to protect the apparatus stored in theinner pipe as it is introduced down a casing 94. When the unit reachesthe bottom of the casing, the inside pipe is raised slightly and turnedto cause lug 93 to come out of I hook 92. The inner or carrier pipe maythen be dropped or pushed down through the outer pipe as shown in FIG-URE 2 exposing or releasing the internals via opening 95 to the cavity95 communicating with casing 94. Means such as how springs 96 suspendthe outer pipe in the casing to hold the outer pipe in position as theinner pipe is moved independently.

As the inner pipe 91 is pushed down through the outer pipe 90, slips 97ride up on mandrel 98 and bite into the casing wail to anchor the outerpipe even more firmly into position. The thus firmly anchored outer pipeoffers sufficient resistance to the downward movement of the expandablepacker 99 to cause it to expand to contact the casing wall (FIGURE 2).The expanded packer provides a complete seal of the annulus between theinner pipe 91 and the casing 94. Fluids introduced through this annulusare thus directed through the carrier to the apparatus, e.g., flexibletubes or telescoping tubes, contained therein. As in other embodiments,internal tubing 100 is conveniently disposed through the assembly toprovide a second fluidizing conduit if desired. An extension 101 of thetubing is sometimes employed to locate the terminus of this secondfluid-carrying conduit at a predetermined elevation in the cavity.

The apparatus of the present invention is provided through a bore holeby any convenient means. Often tubing passes through the carrier and isattached thereto. The apparatus is then pushed through the casing by thetubing. In other embodiments, the carrier is attached to liner and theliner is suspended from the casing by packing means. 'By liner is meanta conduit which is disposed inside a casing but extends only a portionof the length of the casing, typically from the cavity only a few feetup the casing. Tubing refers to similar conduits which extend from theearths surface down through the casing. Liners are set in a casing byWell known techniques on tubing strings or by means of wire lines.

The hatches of the claimed apparatus are openings of any convenient sizeand shape. There may be one or a plurality of such hatches in a givenapparatus. A hatch may be covered with a door for added protection. Thedoor, typically a removable section of the carrier, may be mechanicallybiased by means provided for that purpose. Alternatively, the doors maybe removed in response to electrical or magnetic impulses or any othersuitable means. Opening of the hatches is usually correlated withemergence of the apparatus from a easing into a cavity. It is Withincontemplation that the opening point, '*e.g., when correlated with someother reference the carrier strikes the'bottomof the cavity or reaches apre-determined pressure or temperature environment in the cavity.

Orientation means are often included in association with the carrierassemblies of this invention. Means within contemplation include simplehinge means adjusted to stop or lock in a predetermined position as thedown hole device falls from the carrier. More sophisticated means may beemployed when it is desired to adjust from time to time the orientationof the device with respect to horizontal or with respect to the pointsof the compass. Such means will readily suggest themselves to theskilled art and the invention is not limited in scope to the specificmeans illustrated in the drawings.

The dimensions of the claimed apparatus are restricted only by theheight of the cavity and the diameter of the bore hole casing throughwhich it is emplaced in the cavity. Thus, the outer diameter of thecarrier need be only very slightly smaller than the internal diameter ofthe casing. The total height of the carrier may be even greater than theheight of the cavity provided the top of the hatch is below the bottomof the casing when the carrier touches the bottom of the cavity. In acavity 50 feet high, for example, a carrier nearly 50 feet long may beconveniently employed. If it is desired to relocate the down holemechanism near the top of the cavity after it has been released near thebottom of the cavity, the carrier need merely be partially withdrawn upthe bore hole.

What we claim is:

1. Apparatus for protectively introducing a device through a bore holecasing to a subterranean cavity comprising a container formed by twoconcentric pipes, the inner of said two concentric pipes beingconstructed to house said device and provided with an opening suitablefor introducing said device into said cavity, the outer of saidconcentric pipes forming a cover for said opening, means associated withsaid concentric pipes to separate them from each other in a verticaldirection to thereby expose the opening of said inner pipe and providecasing for said device from said inner pipe to said opening and meansoperably associated with said inner pipe to provide for firmly attachingthe outer pipe to the wall of the bore hole casing when the inner pipeis moved away from the concentric outer pipe in a vertical direction.

2. The apparatus of claim 1 wherein said device is selected from thegroup consisting of solvent supply systems, flexible conduits, fluidflow diverters, electronic measuring devices, sample retrieval devicesand photographic equipment.

3. The apparatus of claim 1 wherein the device includes a telescopingrigid conduit.

of the hatch be References Cited UNITED STATES PATENTS 2,106,859 2/1938Spang 166l38 2,251,916 8/ 1941 Cross 299-5 3,191,684- 6/1965 Pittman etal. 166-216 ERNEST R. PURSER, Primary Examiner U.S. Cl. X.R. 299l7;166l17

